STM images of graphene, graphite and Silicon carbide

[qoquqoqu]

most STM images of graphite have been acquired using a bias voltage of ? Or in the range ?
Same thing for graphene and Silicon carbide

 

[eljose79]

Thank you for your question. The majority of STM images of graphite have been acquired using a bias voltage in the range of -1 to +1 volts. This range allows for the imaging of individual atomic layers within the graphite structure. For graphene, a bias voltage of -2 to +2 volts is typically used to image the individual carbon atoms in the hexagonal lattice. The choice of bias voltage can also depend on the specific experimental setup and the desired resolution.

For Silicon carbide, a bias voltage of -2 to +2 volts is also commonly used to image the individual atoms in the crystal lattice. However, higher bias voltages (up to +5 volts) may be necessary to image the surface defects and impurities in the material.

It is important to note that the choice of bias voltage can affect the contrast and resolution of the STM images. Lower bias voltages can result in better resolution but may also lead to a weaker signal, while higher bias voltages can provide a stronger signal but may also introduce artifacts or damage the sample.

In conclusion, the choice of bias voltage for STM imaging depends on the specific material being studied and the desired resolution and contrast. It is important for scientists to carefully select and optimize the bias voltage for each experimental setup to obtain the most accurate and informative images.